I am trying to write a short description of unicorn. There are few points I can’t seem to express well. I’d appreciate your corrections or feedbacks. Thank you for your time.

--------What is a unicorn? The Unicorn is one of the most mysterious of all the animals. The only thing everyone agrees on is that it has the appearance of a horse with a single horn in the middle of its forehead.

Unicorns have been featured in folk tales, novels, classical literature, poems, and stories for centuries. In Chinese mythology, the unicorn was an animal of good omen that came to humans only on important missions. Seeing it around was a sign of good times, and the fact that it has not been seen in many centuries suggests that we are living in “bad” times.

It is believed that it will appear once again when the time is right and when there is goodness in the world.---------

一角獣（ユニコーン）は何ですか?一角獣（ユニコーン）は動物界で最も神秘的の一つです動物のうちで一角獣は最も神秘的の一つです。最も神秘的な動物の1つです。(Will this sentence become "one of the most mysterious animals"?)皆が同意する唯一のことは、額の中央に単一の角の馬の外観を持っているということです。

一角獣は何世紀もの間、民話、小説、詩、古典文学、および物語に・で載っています。1) にorで2) not sure how to express “have been featured”

Unicorn is a special creature, like 麒麟。 If I ever had free time, I would write about 麒麟. In fact, I read many stories about 麒麟 when I was a kid. But, there are many high-level kanji involved, which I am not confident of using them. I will learn those grammar points and see if I can apply the usage.

*******I want to say, 麒麟 once appeared during 春秋戦国時期, but it was caught and killed by the people. 孔子 (Confucius) regarded 麒麟 as an auspicious creature, it symbolized benevolence and justice, he was very sad when he saw this.

Confucius was very sad when he saw the kirin killed by the people during that time.>> その時、人々によって麒麟が殺されるのをみた孔子はすごく悲しんだ。